The swift pace of discovery of new gene products by genomics and proteomics efforts and the growing availability of vast repositories of genes necessitates a strategy for analyzing proteins in a high-throughput manner. The high-density array format lends itself well to ordered high-throughput experimentation and analysis and has therefore become an established and widely-used format for high-throughput analysis of nucleic acids. Nucleic acid microarrays have enabled researchers to compare the expression of thousands of genes simultaneously.